Belt attachment device and method

ABSTRACT

A conveyor belt assembly including a flexible belt body with a plurality of spaced flexible teeth and at least one hardened tooth coupled to the belt body. The flexible belt body and flexible teeth comprise a resilient material. The hardened tooth comprises hardened plastic or metal. The flexible belt body also includes at least one reinforcing member within the belt body. A guide member is coupled to the flexible belt body and the hardened tooth to assist in transporting objects on the conveyor belt assembly. A pivotable clamping device clamps the ends of the belt body together to form a continuous belt. The clamping device clamps the reinforcing member to ensure a strong connection.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.10/407,379, filed Apr. 4, 2003, now U.S. Pat. No. 6,896,125, the entirecontents of which is hereby incorporated by reference herein.

BACKGROUND

The invention relates to conveyor belts, and more particularly tomethods of attaching objects to conveyor belts.

It is known in industries utilizing conveyor belt systems tomechanically attach items, such as baskets or bins, to conveyor belts toassist in moving objects from one point to another. The prevalent methodof making attachments to conveyor belts is to glue or “weld” theattachments onto the belt. However, the bond created in this type ofattachment often fails under heavy loads.

Another issue with conveyor belt systems is facilitating the removal andreplacement of conveyor belts to replace worn or broken segments of thebelt. In systems where an endless belt is used, an “endless” belt iscommonly formed by splicing two ends of a belt together by serrating theedges and gluing the ends together. By gluing the ends together, itbecomes difficult to remove and replace a conveyor belt. Often, theconveying machine must be disassembled to allow for removal andreplacement of the belt.

SUMMARY

The present invention provides a conveyor belt assembly that facilitatesmounting items to the belt. The assembly includes a flexible belt bodywith a first (outer) surface and a second (inner) surface. A pluralityof flexible teeth (e.g. made of rubber) are positioned on the secondsurface for engagement with a toothed sprocket. At least one hardenedtooth (e.g. hard plastic or metal) is also coupled to the second surfaceof the belt body to provide a location for attachment of an item to thebelt.

In one embodiment, the hardened tooth has a cavity (e.g., a threadedhole) and the flexible belt body has a hole aligned with the cavity suchthat a fastener can be inserted through the hole and into the cavity tocouple the hardened tooth to the belt body. The fastener can also beused to attach a guide member adjacent to the first surface of the beltbody by inserting the fastener through the guide member, through thehole, and into the cavity in the hardened tooth.

The above-described conveyor belt assembly can be formed by a novelmethod. The method includes forming a belt having a body and a pluralityof teeth of a flexible material, creating a space between two of theflexible teeth, and positioning a hardened tooth in the space. Themethod can further include positioning a guide member adjacent the beltbody aligned with the tooth and attaching the guide member to thehardened tooth.

In another aspect, the invention provides a conveyor belt assemblyhaving a high-strength coupling mechanism that facilitates attachmentand detachment of the belt ends. The assembly includes a flexible beltbody with first and second ends and a pivotable clamping device couplingthe first and second ends into a continuous belt surface. In oneembodiment, the assembly includes a plurality of flexible teeth mountedto the belt body and at least one reinforcing member (e.g., steelcables). The pivotable clamping device preferably includes a first clampwith first upper and lower portions and a second clamp with second upperand lower portions, the first and second clamps being pivotally coupledto each other. The first and second upper portions can include a recessthat interacts with a raised area of the first and second lower portionsto bend the reinforcing member around a tight radius to increase theclamping strength. An adhesive can also be applied to the first andsecond lower portions to further increase the clamping strength.

The above-described conveyor belt assembly can be formed by a novelmethod. The method includes forming a belt body out of flexible materialand coupling a pivotable clamping device to the first and second ends ofthe belt body. Preferably, the reinforcing member is exposed at thefirst and second ends of the belt body. Adhesive can be applied to thepivotable clamping device to capture the reinforcing member, increasingthe strength of the clamp. The reinforcing member can then be clamped bythe pivotable clamping device, bending the reinforcing member around atight radius to further increase the clamping strength of the pivotableclamping device.

Other features and advantages of the invention will become apparent tothose skilled in the art upon review of the following detaileddescription, claims, and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of a belt assembly according toone aspect of the present invention.

FIG. 2 is a top view of the belt assembly shown in FIG. 1.

FIG. 3 is a side view of the belt assembly shown in FIG. 1.

FIG. 4 is a bottom view of the belt assembly shown in FIG. 1.

FIG. 5 is an exploded perspective view of a clamping assembly accordingto another aspect of the present invention.

FIG. 6 is a side view of the clamping assembly shown in FIG. 5 engagedwith a toothed pulley.

FIG. 7 is a top view of the clamping assembly shown in FIG. 5.

FIG. 8 is an exploded perspective view of a clamping assembly accordingto another aspect of the present invention.

FIG. 9 is a perspective view of a resilient pulley system for use withthe clamping assembly according to the present invention.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it isto be understood that the invention is not limited in its application tothe details of construction and the arrangement of components set forthin the following description or illustrated in the following drawings.The invention is capable of other embodiments and of being practiced orof being carried out in various ways. Also, it is to be understood thatthe phraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. The use of“including,” “comprising,” or “having” and variations thereof herein ismeant to encompass the items listed thereafter and equivalents thereofas well as additional items. Unless specified or limited otherwise, theterms “mounted,” “connected,” “supported,” and “coupled” and variationsthereof are used broadly and encompass both direct and indirectmountings, connections, supports, and couplings. Further, “connected”and “coupled” are not restricted to physical or mechanical connectionsor couplings.

FIG. 1 illustrates a portion of a conveyor belt assembly 4 according toone aspect of the present invention. The conveyor belt assembly 4includes a flexible belt body 8 with a first surface 12 and secondsurface 16. It should be understood that the terms “first” and “second”are used for convenience to refer to the outer and inner surfaces of thebelt. In the embodiment illustrated in FIGS. 1–4, the flexible belt body8 is an endless belt. It is understood, however, that in otherembodiments, such as the embodiment illustrated in FIGS. 5–7, theflexible belt body 8 may have discrete ends.

As shown in FIG. 1, the first surface 12 of the belt body 8 is a smooth,non-segmented surface. A plurality of flexible teeth 20 are formed withthe belt body 8 on the second surface 16. The belt body 8 and teeth 20are formed of a resilient material, such as rubber. It is understood bythose skilled in the art that the belt body 8 and teeth 20 may be formedof any suitable flexible material, such as flexible plastic or otherelastomeric material.

The illustrated belt body 8 also includes at least one reinforcingmember. In the embodiment shown in FIG. 1, the reinforcing member is aplurality of steel cables 28. It is understood that the reinforcingmember may instead comprise a steel belt, a plurality of Kevlar®strands, or any other suitable reinforcing material. It is alsounderstood that the apparatus and method of the present invention couldbe utilized by a belt assembly 4 that does not include any reinforcingmember.

As shown in FIGS. 1 and 3, one of the flexible teeth 20 is removed fromthe second surface 16 and replaced with a hardened tooth 32. Thehardened tooth 32 may be made of hardened plastic, metal, any othersuitable hardened material, or any combination of these materials. Thehardened tooth 32 has a cavity to facilitate coupling the hardened tooth32 to the belt body 8. In the embodiment of FIG. 1, the cavity is athreaded hole 36 extending through the entirety of the hardened tooth32. But it should be understood that in other embodiments, the cavitymight only extend partially into the hardened tooth 32. In addition, thethreaded hole 36 could be formed by a threaded insert positioned inanother material.

The belt body 8 includes two belt holes 40 to facilitate coupling thehardened tooth 32 to the belt body 8. The belt holes 40 are formedthrough the first and second surfaces 12, 16 and are aligned with thethreaded hole 36 in the hardened tooth 32. Fasteners couple the hardenedtooth 32 to the flexible belt body 8. In the illustrated embodiment, thefasteners are threaded bolts 44.

In the embodiment illustrated in FIGS. 1–4, the belt assembly 4 alsoincludes a guide member 48 coupled to the first surface 12 of the beltbody 8. The guide member 48 allows other objects, such as a basket, abin, or a shelf (not shown), to be attached to the belt body 8 to assistin transporting goods with the assembly 4. The guide member 48 has twoholes 52 aligned with the belt holes 40 in the belt body 8 and with thethreaded holes 36 in the hardened tooth 32. As shown in FIG. 1, theguide member 48 is coupled to the belt body 8 by the bolts 44. Bycoupling the guide member 48 to a hardened tooth, a stronger mechanicalconnection is made allowing the conveyor belt assembly 4 to moreeffectively transport heavy loads.

It should be understood that in other embodiments (not shown) the guidemember 48 could be coupled to the hardened tooth 32 without the use ofthe threaded bolts 44. In these embodiments, there would be no belt hole40, nor would there be a need for the hole 36 in the hardened tooth 32.Instead, the guide member 48 could be coupled to the hardened tooth 32by a coupling member, such as a metal strap, around the side of the beltbody 8. The coupling member would be attached at one end to the hardenedtooth 32 and at the other end to the guide member 48. By attaching theguide member and hardened tooth in this manner, a belt of lesserthickness could be used to achieve the same belt strength because therewould be no hole formed through the belt.

As noted above, FIG. 1 illustrates a portion of the conveyor beltassembly 4 of the present invention. The portion illustrated in FIG. 1may be repeated in spaced increments across the length of the beltassembly 4 to allow for multiple guide members 48 to be attached to theflexible belt body 8. This would require removing one of the flexibleteeth 20 at spaced increments and replacing the flexible tooth 20 with ahardened tooth 32.

The conveyor belt assembly 4 can be made by the following process.First, a belt body 8 and a plurality of teeth 20 are formed out of aflexible material. As shown in FIGS. 1–4, the belt body 8 is reinforcedwith a plurality of steel cables 28. A space 54 is created between twoadjacent flexible teeth 20 to facilitate coupling an object to the beltbody 8. The space 54 may be created by removing a flexible tooth 20 fromthe belt body 8 (as shown in FIGS. 1 and 3) or by forming the belt body8 with a tooth missing. A belt hole 40 is formed in the belt body 8aligned with the space 54. A hardened tooth 32 is aligned in the space54 adjacent the belt body 8. A guide member 48 is then positionedadjacent the belt body 8 in opposing relation to the hardened tooth 32.A threaded hole 36 is formed in the hardened tooth 32 and a threadedbolt 44 is inserted through the guide member 48 and the belt hole 40into the threaded hole 36 in the hardened tooth 32, thereby coupling theguide member to the hardened tooth 32.

FIG. 5 illustrates another assembly that embodies the second aspect ofthe present invention. The flexible belt body 8 includes a first end 56and a second end 60. The conveyor belt assembly 4 further includes apivotable clamping device 64 that couples the first and second ends 56,60 of the belt body 8 to form the belt body 8 into a continuous loop. Inother embodiments (not shown), the first end of one belt body portionmay be connected to the second end of a second belt body portion, thefirst end of the second belt body portion connected to the second end ofa third belt body portion (and so on) to create a continuous beltassembly of multiple belt body portions. This arrangement provides bothcontinuity in the belt and ease of removal of any given belt portionshould that portion need repair.

The pivotable clamping device 64 includes a first clamp having a firstupper portion 68 and a first lower portion 76, and a second clamp havinga second upper portion 72 and a second lower portion 80. The first upperportion 68 and the first lower portion 76 are coupled to the first end56 of the belt body 8, and the second upper portion 72 and the secondlower portion 80 are coupled to the second end 60 of the belt body 8.

The first and second upper portions 68, 72 are identical with respect toeach other, and the first and second lower portions 76, 80 aresubstantially identical, with the exceptions noted below. Therefore,only the first upper portion 68 and first lower portion 76 will bedescribed in detail. The first upper portion 68 includes two openings 84that allow the insertion of a fastener in the form of a bolt 88 tocouple the first upper portion 68 to the first lower portion. The firstupper portion 68 also includes a recessed area 90 that cooperates withthe first lower portion 76 to increase the clamping strength of theclamping device 64. The first upper portion 68 also includes a pluralityof ridges 94 that cooperate with the first lower portion 76, as will bedescribed in detail below.

The first lower portion 76 includes two cavities in the form of threadedholes 92 that are aligned with the openings 84 in the first upperportion 68. The first lower portion 76 includes a first surface 96including a raised area 100 that fits with the recessed area 90 of thefirst upper portion 68 to increase the clamping strength of the clampingdevice 64. The first surface 96 further includes a plurality of ridges102 that cooperate with the ridges 94 of the first upper portion 68,also increasing the clamping strength of the clamping device 64.

As illustrated in FIGS. 5–7, the first lower portion 76 includes asecond surface 104 that includes a generally tooth-shaped protrusion108. The generally tooth-shaped protrusion 108 facilitates the travel ofthe portion of the belt assembly 4 that includes the clamping device 64around a tooth-receiving portion or pulley 110 of a conveyor. Referringto FIGS. 5 and 6, as the belt body 8 travels around the pulley 110, itis the first flexible tooth 20 that is immediately adjacent each of theends 56, 60 of the belt body 8 that supports the belt body 8 andmaintains the proper position of the belt body 8 as the belt body 8travels around the pulley 110. The elastic behavior of the teeth 20allows the load to be distributed to a number of elastic teeth 20. Thetooth-shaped protrusion 108 mimics the tooth-shape but is undersized soas not to interfere with the elastic behavior of the teeth 20. Thoseskilled in the art will also understand that the tooth-shaped protrusion108 is not necessary at all for the belt assembly 4 to travel around thepulley 110.

The illustrated clamping device 64 also includes a central hinge member112, shown in FIG. 5 being integrally formed with the lower portions 76,80 of the clamping device 64. The central hinge member 112 allows theclamping member 64 to flex or pivot as it travels over any roundedportion of the path of travel of the conveyor belt assembly 4. Asillustrated in FIGS. 5 and 6, the central hinge member 112 of the secondlower portion 80 has a generally tooth-shaped portion 114 that extendsinto the pulley 110 of the conveyor to further facilitate the travel ofthe clamping device 64 around the pulley 110. Again, this tooth-shapedportion 114 is undersized compared to the elastic teeth 20 so that thetooth-shaped portion 114 will not interfere with the operation of theelastic teeth 20. Those skilled in the art will understand that thetooth-shaped portion 114 is not necessary for the belt assembly 4 totravel around the pulley 110. A pin or fastener 116 is inserted throughthe central hinge member 112 to couple the lower portions 76, 80 of theclamping device 64 together, thereby coupling the first and second ends56, 60 of the belt body 8 into a continuous loop.

As shown in FIG. 5, to ensure that the clamping device 64 is coupled tothe belt body 8 with sufficient strength, a portion of the belt bodymaterial is removed from the ends 56, 60 to expose the steel cables 28within the flexible belt body 8. The steel cables 28 are insertedbetween the upper and lower portions 68, 76 of the clamp such that theclamping device 64 is coupled directly to the steel cables 28. Anadhesive, such as a high-strength epoxy adhesive, may be applied to thelower portion 76 of the clamping device 64 to capture the cables andincrease the strength of the clamp. The engagement of the raised area100 and the recessed area 90 acts to bend the steel cables 28 around thetight radius of the raised area 100. The radius of the raised area 100is less than about 0.25 in., preferably less than about 0.15 in., and inthe illustrated embodiment the radius measures about 0.094 in. Theradius of the recessed area 90 is less than about 0.3 in., preferablyless than about 0.25 in., and in the illustrated embodiment the radiusmeasures about 0.125 in. This bending facilitates a better engagement ofthe clamping device 64 with the steel cables 28 to increase the strengthof the coupling.

The ridges 94, 102 of the first upper portion 68 and first lower portion76 also clamp together, bending the steel cables 28 along the ridges 94,102, thereby further increasing the clamping strength of the clampingdevice 64. The engagement of the aforementioned ridges 94, 102 with theaddition of the adhesive increases the clamping strength of the clampingdevice 64 in that in order to release the belt ends 56, 60 from theclamping device 64 unintentionally, not only must the steel cables 28 bestripped out from between the upper and lower portions of the clampingdevice 64, but the adhesive must also shear to release the cables 28.

As shown in FIG. 6, the bolts 88 are inserted through the upper portions68, 72 at the point of the recessed area 90, further adding to thestrength of the coupling by putting the greatest clamping pressure onthe point where the steel cables 28 are bent by the engagement of therecessed area 90 and the raised area 100. The bolts 88 are insertedthrough the openings 84 of the upper portions 68, 72 and received in thethreaded holes 92 to clamp the ends 56, 60 of the belt body 8 together.

Using the above structure, the first and second ends 56, 60 of the beltbody 8 can be attached according to the following process. A portion ofthe flexible material of the belt body 8 is removed at the first andsecond ends 56, 60 to expose the steel cables 28. An adhesive is appliedto the inner surfaces of the clamping device 64. The first and secondends 56, 60 of the belt body 8 are inserted into the respective clamps,and the cables 28 are fed between the respective raised portions 100 andrecessed portions 90 and are captured by the adhesive. The bolts 88 arethen inserted and tightened to clamp the clamping device 64 to the beltbody 8. The clamping device 64 is thus coupled directly to the steelcables 28.

It should be understood that the embodiment illustrated in FIGS. 5–7 maybe used in combination with other embodiments, such as the embodimentillustrated in FIGS. 1–4, or it may be used alone. Similarly, theembodiment illustrated in FIGS. 1–4 may be used alone or in combinationwith other embodiments. For example, as shown in FIG. 8, the guidemember 48 could be secured directly to the clamping device 64, obviatingthe need for attaching a hardened tooth 32 to the belt body 8. In thisembodiment, the holes 52 in the guide member 48 are aligned with theopenings 84 in the first upper portion 68 of the clamping device 64. Byso doing, the bolts 88 are used to both secure the guide member 48 tothe clamping device 64 and to clamp the first upper and lower portions68, 76 together, securing the steel cables 28 of the belt body 8 betweenthem.

With reference to FIG. 9, it is also understood by those of skill in theart that the above described method of connecting or attaching belts,such as the clamping device 64, will form a bump that passes over thepulley during the reverse bending of the belt in certain systems.Reverse bending of the belt occurs, for example, when the belt accordingto the present invention is used in a lift mechanism. In such amechanism, the guide member 48 is used to support a lift platform 118.The path of the belt through the lift mechanism commonly results inreverse bending of the belt, as illustrated in FIG. 9. One solution (notshown) is to form pockets in the rigid pulley that would provideclearance for the clamping device 64 during the reverse bending of thebelt. This can be complicated due to the timing required to position theclamping assembly 64 within the clearance in the rigid pulley.

Another solution, illustrated in FIG. 9, is to utilize a resilientpulley in the conveyor system to allow the clamping device 64 to passduring reverse bending of the belt. In the illustrated embodiment, theresilient pulley is a pneumatic tire 120. As the clamping device 64passes over the tire 120 during reverse bending of the belt, the tire120 deflects, allowing the clamping device 64 to pass over the tire 120without damaging the clamping device 64 or disrupting the motion of thebelt. A resilient pulley, such as the tire 120, also provides for shockabsorption in the event that a load crashes, minimizing the potentialfor damage to the equipment. The tire 120 also provides more time forthe electronic sensors (not shown) in the equipment to detect anoverload condition due to a load crash and to shut down the drive systemin response. The pneumatic tire 120 also automatically compensates forany stretching or wear of the belt or the steel cables 28 within thebelt body 8 caused by use or by settling of the wires in the steelcables 28. Prior systems utilizing rigid pulleys and chain-driven beltsrequire periodic adjustments for chain wear. The tire 120 performs thesetypes of adjustments automatically.

The embodiments described above and illustrated in the drawings arepresented by way of example only and are not intended as a limitationupon the concepts and principles of the present invention. As such, onehaving ordinary skill in the art will appreciate that various changes inthe elements and their configuration and arrangement are possiblewithout departing from the spirit and scope of the present invention asset forth in the following claims.

1. A conveyor belt assembly comprising: a flexible belt body having afirst surface and a second surface; a plurality of spaced flexible teethpositioned on the second surface of the flexible belt body; at least onehardened tooth coupled to the second surface of the flexible belt body;and a guide member to assist in transferring goods disposed on the firstsurface of the flexible belt body and coupled to the at least onehardened tooth.
 2. The conveyor belt assembly of claim 1, wherein thehardened tooth has a cavity.
 3. The conveyor belt assembly of claim 2,further comprising a hole in the flexible belt body aligned with thecavity in the hardened tooth such that a fastener can be insertedthrough the hole into the cavity to couple the hardened tooth to theflexible belt body.
 4. The conveyor belt assembly of claim 3, whereinthe guide member includes a hole aligned with the hole in the flexiblebelt body and the cavity in the hardened tooth such that a fastener canbe inserted through the holes and the cavity to couple the guide memberto the hardened tooth.
 5. The conveyor belt assembly of claim 2, whereinthe cavity within the hardened tooth is a hole extending through theentirety of the hardened tooth.
 6. The conveyor belt assembly of claim5, wherein the hole is threaded.
 7. The conveyor belt assembly of claim1, wherein the flexible belt body and the flexible teeth comprise thesame material.
 8. The conveyor belt assembly of claim 7, wherein theflexible belt body and the flexible teeth comprise a resilient material.9. The conveyor belt assembly of claim 1, wherein the hardened toothcomprises plastic.
 10. The conveyor belt assembly of claim 1, whereinthe hardened tooth comprises metal.
 11. The conveyor belt assembly ofclaim 1, wherein the flexible belt body is an endless belt body.
 12. Theconveyor belt assembly of claim 1, further comprising at least onereinforcing member within the flexible belt body.